Air Filters

[78yamahaman]

I have a 78xs1100e that I recently purchased. I have been having alot of carb problems with the bike. I was wondering to make things easier on myself since I have been pulling them and putting them back on so much if I could just get rid of the air box and put individual filters on each carb. All of the individual filters I see say 79 and up none of them say 78???? The problem I am having is the number 1 and 2 carbs are spitting fuel back into the air box. I have pulled the needles and the floats a few times and everything seems to be working right but when I put them back on here comes the gas again? Any ideas? Thanks for all the help.

[mro]

I take it that you've put new needles and seats in the carbs and still have fuel leaking.

Have you checked that the floats are ok and don't have any holes in em?
What condition fuel tank. Rust etc in it?
Takes but a tiny partical stuck between needle and seat to make it leak.
Float height (25.7 mm) if to high or low can cause floats to hang up. Sometimes float can drop too far and it can get stuck aginst side of float bowl.

Carbs up side down on bench with bowls off.
Hook up a fuel supply.
Lift float to allow fuel in to carb then let it back down.
Weight of float should stop fuel flow. If stopped check it again half hour later. Will also let you know if fuel is getting past the washer under needle seat.

As for pod filters, use the search feature.
Seems that the ones from mikesxs.com are pretty good.


mro

[stoked]

Fortunently the XS11 takes the pods well. The stock air box apparently flows as well as pods. Personally I like the way bikes look better with pods than bulky air boxes. And it's a lot easier to get to the carbs. I used to take them off once or more a month to clean so they have been invaluable. I now have inline filters and haven't had the need to clean carbs in a long time. But I am replacing the filters about once a month. They start as a nice gold color and are black a few weeks later. My tank is apparently very dirty.

[dbeardslee]

If you're having a problem with 1 and 2, they share a fuel line. Had a similar problem with mine and it wound up being the petcock that fed those carbs. Even with brand new needle and seats, with a full tank of gas there was sufficient pressure to load up the carbs. Fixed the petcocks and the problem went away. Have you checked yours to make sure they shut-off the fuel supply when there is no vacuum present?

[78yamahaman]

Thanks guys for the help. I made a major mistake today. I was pulling the floats and broke the the part that holds the pin in to the float. Anyone have a number 2 carb for a 78e they would like to sell I just need the body. I have new needles and seats but now I need a new carb body. The reason I say number 2 is its the carb with the vaccum on it.

[trbig]

Some people have had success in repairing the float posts with different methods. I overheard it discussed at the Meeting of the Minds, that the old (As in original formula) JB Weld works well... but there may be a problem with the fast setting type being submerged in fuel??

The easiest way would be another carb body if you can find one.... or a whole set off Ebay and use yours for parts. But just realize that yours may not be junk yet.


Tod

[dbeardslee]

Ken Talbot had a float post repair pic in this thread. Seems like someone cut off the broken part and threaded an old jet into it, then cross-drilled. Be a lot cheaper than a new carb, and probably stronger as well.

[78yamahaman]

Thanks again. I am going to keep looking but probably not to long before I try the fix method. Thanks again for all the responses and the help.

[chrisso]

Hi All. Ive got a '80 XS11 and have been thinking of ditching the airbox & ffitting pods-but i like the look of the chrome on the outside of the AB.Would I get more power with pods & would it need rejetting? I would rather leave it standard if theres not much power increase-Thanks

[John]

If you like the looks of the airbox, but want more airflow, then just drill a couple of 1/2 inch holes in the bottom of the airbox, but be sure they are in the unfiltered (inner) side of the filter. That way the extra air will be filtered also.

[chrisso]

Originally posted by John
If you like the looks of the airbox, but want more airflow, then just drill a couple of 1/2 inch holes in the bottom of the airbox, but be sure they are in the unfiltered (inner) side of the filter. That way the extra air will be filtered also.

No other mods neccessary? PS-like your Avatar, im a big Roger Dean fan too